Attention-guided Convolutional Neural Network for Lightweight JPEG Compression Artifacts Removal

JPEG compression artifacts seriously affect the viewing experience. While previous studies mainly focused on the deep convolutional networks for compression artifacts removal, of which the model size and inference speed limit their application prospects. In order to solve the above problems, this paper proposed two methods that can improve the training performance of the compact convolution network without slowing down its inference speed. Firstly, a fully explainable attention loss is designed to guide the network for training, which is calculated by local entropy to accurately locate compression artifacts. Secondly, Fully Expanded Block (FEB) is proposed to replace the convolutional layer in compact network, which can be contracted back to a normal convolutional layer after the training process is completed. Extensive experiments demonstrate that the proposed method outperforms the existing lightweight methods in terms of performance and inference speed.